Grinding-machine.



No. 774,612. PATENTED NOV. 8, 1904. E. STEAD. GRINDING MACHINE.APPLICATION FILED JUNE 7, 1904.

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GRINDING-MACHINE.

SPECIFICATION forming part of Letters Patent No. 774,612, dated November8, 1904.

Application filed June 7, 1904:. Serial No. 211,523. (No model.)

ments in Grinding-lvlachines, of which the following is a specification.

This invention relates to grinding-m achines, the object of theinvention being to provide a chuck or holder for receiving and properlysustaining the grinding-disks, the construction of the chuck or holderbeing such that a grinding-disk of concavo-convex form in cross-sectionmay be reversed to present either side for grinding, the chuck and diskbeing so constructed and related to each other that the disk is properlysustained in either position and thoroughly supported in order toinsurethe best results during the grinding operation and held against rotationrelatively to the chuck or holder in which it is mounted.

With the above and other objects in view, the nature of which will morefully appear as the description proceeds,the invention consists in thenovel construction, combination, and arrangement of parts, as hereinfully described, illustrated, and claimed.

In the accompanying drawings, Figure 1 is a side elevation of the chuckor holder embodying the present invention, showing a grinding-diskmounted therein with the convex side thereof presented as a workingsurface. Fig. 2 is a central vertical section through the same, showingthe grinding-disk reversed in its position as compared with Fig. 1. Fig.3 is a detail edge view ef thengrinding-disk, showing the annular flangethereof.

Like reference-numerals designate corresponding parts in all the figuresof the drawings. V

The chuck or holder contemplated in this invention somewhat resembles anordinary houra glass, the upper body portion 1 thereof beingsubstantially conical in shape and reversely disposed to the lowerportion 2 thereof, which is more of a hemispherical shape, the outersurface thereof being rounded to form a hood or rim which extendsconsiderably outside of and around the actuating-spindle 3, thusprotecting the bearings of the machine of which ranged a sleeve 4,preferably tapered inside,

adapting it to fit upon a correspondinglytapered upper extremity of thespindle 3, as

, shown in Fig. 2.

The upper portion of the body 1 is preferably in the form of a truecylinder, as shown at 5, and the extreme upper edge thereof is rabbeted,as shown at 6, to form an annular shoulder or ledge 7, upon which thegrindingdisk 8 finds its support.

The grinding-disk may be of any suitable shape or form in cross-section,the one illustrated in the drawings being concavo-convex or beingprovided with one convex surface and one concave surface, both surfacesbeing used for grinding purposes. in carrying out the present inventionthe disk is provided with an annular circumferential flange 9, whichextends entirely around the body of the disk and is provided at asuitable point with an offset, preferably in the form of an integral keyor projection 10, while the upper portion 5 of the chuck or holder isprovided with a slot or key-seat 11, in which the offset or key 10 isreceived, thus preventing relative rotative movement between thegrinding-disk and the chuck or holder. The construction just describedalso adapts the disk to be readily removed and, reversed and replaced inthe chuck or holder.

The improved chuck or holder hereinabove described is especially adaptedfor holding disks used in grinding lenses, and by reason of the factthat the disk is capable of being reversed one chuck will answer thepurposes of many, as awhole set of disks having grinding-surfaces atdifferent curves, contours, or pitches may be interchangeably appliedand used in connection with the chuck or holder, thus effecting a savingin material, labor, and time.

Having thus described the invention, what is claimed as new is 1. Thechuck or holder embodying a rabbeted edge, the combination with agrindingdisk having an upper and lower grinding-surface, said disk beingprovided with a circumferential flange to be inserted in the rabbe'tededge portion of the chuck to present either grinding-surface of the diskfor operation.

2. A chuck or holder embodying a rabbeted edge portion and a key-seat insaid portion, the combination with a grinding-disk provided with acircumferential flange, said disk having an upper and a lowergrindingsurface and being provided with a projecting key, said flangeand key cooperating with the rabbeted portion and key-seat of theholder, to present either grinding-surface of the disk for operation.

3. A chuck or holder provided with a rabbeted edge portion, andavprotecting rim or hood embracing the spindle-receiving portion of thechuck, in combination with a grinding disk embodying a circumferentialflange removably fitted in the rabbeted portion of the holder wherebythe grinding-disk is made're- U versible, substantially as. described.

4:. A chuck or holder for the purpose described embodying upper andlower portions flaring in opposite directions, one of said portionsbeing rabbeted in its extreme edge to form a seat, and a grinding-diskprovided with a circumferential flange removably fitted in said rabbetedseat, the grinding-disk being reversible with respect to the chuck,substantially as described.

In testimony whereof ll afix my signature in presence of two witnesses.

ERNEST STEAD.

Witnesses:

HULBERT A. LACEY, THOMAS E. KATTELL.

